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Chapter 1. Understanding Medical Errors

Growing Concerns About Medical Errors

The IOMís release of To Err is Human brought medical errors and patient safety the attention it has long needed but never had. The information presented in the report is not new. Indeed, many studies, some as early as the 1960s, showed that patients were frequently injured by the same medical care that was intended to help them (Schimmel, 1964). While evidence of medical error has existed for some time, the report succeeded in capturing the publicís attention by revealing the magnitude of this pervasive problem and presenting it in a uniquely compelling fashion. The IOM estimates that medical errors cause between 44,000 and 98,000 deaths annually in the United States. Using the more conservative figure, medical errors rank as the eighth leading cause of death, killing more Americans than motor vehicle accidents, breast cancer, or AIDS. In addition to this extraordinary human toll, medical errors result in annual costs of $17 to $29 billion in the United States (Institute of Medicine, 1999). Additionally, fear of becoming a victim of medical error may lead patients to delay obtaining potentially beneficial medical care, which may allow their illnesses to worsen.

Experiencing harm as a result of receiving health care is a growing concern for the American public. Front-page articles in newspapers, television exposes, and cover stories in magazine have provided the stark details of the latest and most dramatic examples of medical errors. Until recently, the perception of medical errors among health care providers and the public has been shaped by these anecdotes, and remedies have focused on fixing blame on individual providers, including health plans, hospitals, doctors, pharmacists, nurses, and other caregivers. That approach, however, has proven ineffective in addressing patient safety, as documented by the ongoing problems noted in the IOM report. The IOMís recommended alternative approaches and other ways in which the Federal agencies can work to reduce medical errors are described in this report.

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Definitions and Context

The lack of standardized nomenclature and a universal taxonomy for medical errors complicates the development of a response to the issues outlined in the IOM report. A number of definitions have been applied to medical errors and patient safety. In To Err is Human, the IOM adopted the following definition:

An error is defined as the failure of a planned action to be completed as intended or the use of a wrong plan to achieve an aim.

In an effort to thoroughly consider all of the relevant issues related to medical errors, the QuIC expanded of the IOM definition, as follows:

An error is defined as the failure of a planned action to be completed as intended or the use of a wrong plan to achieve an aim. Errors can include problems in practice, products, procedures, and systems.

The explicit acknowledgment of the broad scope of errors reflected in this definition respects the responsibilities and capabilities of the Government agencies and departments contributing to this report. The term "patient safety" as used here applies to initiatives designed to prevent adverse outcomes from medical errors. The enhancement of patient safety encompasses three complementary activities: preventing errors, making errors visible, and mitigating the effects of errors.

It is critical to recognize that not all bad outcomes for patients are due to medical errors. Patients may not be cured of their disease or disability despite the fact that they are provided the very best of care. Additionally, not all adverse events that are the result of medical care are, in fact, errors. An adverse event is defined broadly as an injury that was caused by medical management and that resulted in measurable disability (Leape, 1991). Some adverse events, termed "unpreventable adverse events," result from a complication that cannot be prevented given the current state of knowledge. Many drugs, even when used appropriately, have a chance of side effects, such as nausea from an antibiotic. The occurrence of nausea would be an adverse event, but it would not be considered a medical error to have given the antibiotic if the patient had an infection that was expected to respond to the chosen antibiotic. Medical errors are adverse events that are preventable with our current state of medical knowledge. Figure 1 (16 KB) shows this set of possible outcomes of medical care.

In this report, the consideration of errors is broadened beyond preventable adverse events that lead to actual patient harm to include "near misses," sometimes know as "close calls." A "near miss" is an event or situation that could have resulted in an accident, injury, or illness, but did not, either by chance or through timely intervention. Experience in other industries, including aviation, manufacturing, and nuclear energy, demonstrates that there is as much to learn from close calls as there is from incidents leading to actual harm.

It is also important to situate medical errors within the broader context of problems in health care quality. These can be classified under three categories: overuse (the service is unlikely to have net benefit), underuse (a potentially beneficial service is withheld), and misuse (a service is inappropriately used) (Chassin, 1998). The majority of medical errors fall into the category of misuse, but some problems with overuse (e.g., when an unnecessary therapy is prescribed, leading to harm) or underuse (e.g., when an error in diagnosis leads to the failure to apply timely treatment) blur these distinctions. These are related quality problems and may be addressed, in part, by using some of the same approaches. In some cases, however, distinct approaches may be required. That is why the IOM has chosen to deal with the issue of errors separately in its report and plans to issue future reports on underuse and overuse quality problems. Our report will also focus exclusively on errors. Nevertheless, the QuIC participants recognize that the improvements made in patient safety will lay the foundation for, and may encourage, other quality improvements.

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A Framework for Thinking About Errors

There are many possible ways to categorize medical errors, but no universally accepted taxonomy. Classifications have included:

  • Type of health care service provided (e.g., classification of medication errors by the National Coordinating Council for Medication Error Reporting and Prevention).
  • Severity of the resulting injury (e.g., sentinel events, defined as "any unexpected occurrence involving death or serious physical or psychological injury" by the Joint Commission on Accreditation of Healthcare Organizations [JCAHO]).
  • Legal definition (e.g., errors resulting from negligence [Institute of Medicine, 1999]).
  • Type of setting (e.g., outpatient clinic, intensive care unit).
  • Type of individual involved (e.g., physician, nurse, patient).

Implicit in the current variety of classifications is the understanding that different types of medical errors are likely to require different solutions and preventive measures. A single approach to error reduction will fail because it does not account for important differences in types of errors. For example, for the Food and Drug Administration (FDA), product risk category may be a crucial dimension for shaping regulatory policy, but a health care provider may see this dimension as a minor consideration in shaping its error-control methods.

An "ideal" classification of errors would need to be well suited to the purpose to which it is being applied, but there is no single classification system that could be successfully applied to the full set of IOM recommendations being addressed by the QuIC. A framework for reporting may include considerations of the level of reporting (Federal versus State versus organizational), the reasons for which the reporting is being done (learning versus accountability), or the level of injury (near-miss versus minor versus severe). A framework for developing a research agenda may require more focus on the populations involved, available data, and research tools that can be applied to the problem. The experience with the Aviation Safety Reporting System (ASRS), which relies on narrative reporting without a formal framework, demonstrates that rigorous classification may not be necessary at all for some purposes.

The QuIC recommends that the framework for analysis of errors in health care include considerations of how to measure and improve patient safety. As a result, the framework will evolve with each of the initiatives outlined in this report, and the development of classifications to deal with specific purposes will be part of the ongoing work of the QuIC in addressing the IOM recommendations.

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Lessons from Other Industries

As noted in the IOM report, health care is "a decade or more behind other high-risk industries in its attention to ensuring basic safety" (Institute of Medicine, 1999; p. 4). Other sectors of the economy have made remarkable progress in error reduction and safety assurance during the latter part of the 20th century, much of which is attributable to industryís attention to quality management and improvement. In 1986, Motorola instituted a strategy called "Six-Sigma Quality," whose name refers to the Greek letter used to represent standard deviation from the mean of any normally distributed curve (Chassin, 1998). A company which has six-sigma quality experiences only 3.4 defects or errors per million products or events. This is the equivalent of seeing only one misspelled word in about six typical mystery novels or one fumble in 1,600 football games.

Through the six-sigma quality strategy, Motorola, General Electric, and others have substantially reduced their error rates. These companies have systems in place to monitor and report errors and defects so that proper action can be taken, and it is no surprise that these companies are the leaders in their respective industries. Although originally devised for reducing defects in manufacturing plants, the application of the six-sigma quality approach has provided benefits to service industries as well (Chassin, 1998). Service industries have used the six-sigma strategy to analyze, for example, the number of customer complaints that go unanswered after 2 days (per million complaints) or the excess waiting time over 5 minutes a customer encounters before being served (per million customers).

In another example, the aviation industry has adopted quality improvement, safety assurance, and error reduction as its core mission. Currently, airline safety is operating at a five-sigma level (Chassin, 1998). The Federal Aviation Administration (FAA) strategic plan targets a further 80 percent reduction in the airline accident death rate, which would place it close to the six-sigma level. The cornerstone of the FAAís safety initiative has been the ASRS, which was established in 1975. Although the ASRS is funded by the FAA, it is administered by the National Aeronautics and Space Administration (NASA). Many believe that this separation of control over the reporting function to improve safety from the enforcement function is a critical factor in its success. It gives credibility and a sense of safety to the system in the eyes of the many users, particularly those being asked to report their errors and near misses. The ASRS is a vital link between those who observe or experience errors and defects and investigators who have the ability to research and disseminate information regarding these errors. In January 2000 the President signed an executive order providing further protections to reporters under the aviation safety system to enhance information collection. The aviation community (as well as nuclear power and the military communities) has demonstrated the importance of looking critically at human factors and interface design practices in preventing accidents and increasing operating efficiency (Rouse, Kober, and Mavor, 1997).

A review of the experience in non-health-care industries offers some lessons that may be applicable to reducing medical errors. Characteristics of error-reducing industries include:

  • Not tolerating high error rates, and setting ambitious targets for error reduction initiatives.
  • Developing tracking mechanisms that expose errors.
  • Relying on the abundant reports of errors and "near misses."
  • Thoroughly investigating errors, including a root causes analysis.
  • Applying to error reduction a systems approach that embraces a wide array of human factors, technical, and organizational remedies.
  • Focusing on systems solutions that do not seek to find individual fault and blame.
  • Changing the organizational culture so that it enhances safety and error reduction.
  • Allocating adequate resources to error prevention initiatives and the development of the knowledge base to support them.
  • Recognizing that solutions often come from unexpected sources, "out of the box" thinking, and new combinations of disciplines (e.g., human factors psychology with aeronautical engineering).

The QuIC, in reviewing the IOM report as well as these experiences in other industries, has concluded that there is no single "magic bullet" approach to reducing errors, but there is a generalizable approach (that includes the strategies listed above) which, when applied vigorously, is likely to yield favorable outcomes.

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Unique Aspects of Health Care Errors

Research, much of it sponsored by AHRQís predecessor, the Agency for Health Care Policy and Research, documents that the rate of health care errors is far higher than the error rate in other industries. In one study of intensive care units, the correct action was taken 99.0 percent of the time, translating to 1.7 errors per day. One out of five of these errors was serious and/or potentially fatal. If performance levels even substantially better than those found in the ICU (for example, 99.9%, a 10-fold reduction in errors) were applied to the airline and banking industries, it would still equate to two dangerous landings per day at OíHare International Airport and 32,000 checks deducted from the wrong account per hour (Leape, 1994). In these industries, such error rates would not be tolerated.

Health care shares a number of characteristics with these other industries. They all rely on systems which include the interaction of humans and technology to perform a number of functions leading to an outcome (e.g., a safe transcontinental flight, a check correctly deducted from the right account, a patientís recovery from breast cancer). However, health care is distinct in its complexity. For example, a patient in an intensive care unit is the recipient of an average of 178 different activities performed per day that rely on the interaction of monitoring, treatment, and support systems (Leape, 1994). One observer noted that many medical errors can be attributed to the simple fact that the knowledge base to effectively and safely deliver health care exceeds the storage capacity of the human brain (Millenson, 1997).

The decentralized and fragmented nature of the American health care industry contributes to the problem of errors, and will make it a challenge to institute the kind of comprehensive strategy to reduce errors and increase patient safety that the IOM recommends in its report. The work of federally-sponsored researchers such as Lucian Leape and David Bates has illustrated the importance of focusing on the systems of health care delivery in efforts to reduce medical errors. Prescription and delivery of medications provides a dramatic example. It requires the successful completion of at least five interdependent steps: ordering, transcribing, dispensing, delivering, and administering. Inattention to system design leads to numerous opportunities for error in any one of these steps. One study on adverse drug events showed that 78 percent of adverse drug events were due to system failures (Leape, 1995).

Organizational factors are also a distinct challenge in addressing medical errors. Within many hospitals, departments are only loosely linked, and communications between primary care doctors and medical specialists are notoriously poor. As a result, information on problems, as well as improved practices to reduce errors and enhance safety, in one department or one facility do not migrate quickly to others. The variety of settings in which health care is provided (including hospitals, nursing homes, clinics, ambulatory surgery centers, private offices, and patientsí homes) and the transitions of patients and providers among them provide additional challenges.

Errors may be particularly difficult to recognize in health care because variations in an individualís response to treatment is expected. In addition, medical professionals may not recognize that a particular product or procedure may have contributed to or caused the problem because the patient is already ill, the product is not expected to work perfectly at all times, or the event appears unrelated to the product or procedure. Lack of recognition of a serviceís role in adverse events reduces reporting of the association and the opportunity to learn from previous experiences with the product. Because medical errors usually affect only a single patient at a time, they are treated as isolated incidents, and little public attention is drawn to these problems when compared with aviation or nuclear power accidents. Health care errors are also underreported due to liability and confidentiality concerns. These factors explain, in part, the ongoing "invisibility" of medical errors despite the existence of research which has documented their high prevalence.

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Impact of Organizational and Professional Culture

Although the complexity of health care delivery systems is one of the factors distinguishing health care from other industries, the professional culture may pose an even greater challenge than does complexityto improving patient safety. The "naming, blaming, and shaming" approach to dealing with errors has hindered medical error reduction, yet it is the most commonly used approach to addressing errors in health care. In fact, this traditional approach has proven counterproductive—it has driven the patient safety problem underground, leading to an implicit "conspiracy of silence" where problems and close calls are not discussed due to fear of reprisal (Koop, 1999).

Adverse medical events have existed since the beginning of organized medical practice, but may not have been recognized at the time of their occurrence. Bloodletting and toxic "therapies," such as mercurials, led to premature deaths, but these deaths were seen as a reflection of the patientís underlying illness rather than of harmful practice. To some extent, that culture still persists in health care. Although advances in medical technology and knowledge have eliminated these historic practices, errors and mistakes continue to occur at an unacceptably high rate in the delivery of health care. Contrary to popular expectations, doctors, nurses, and other health care professionals are inherently fallible—as are all humans.

The IOM report notes that the majority of medical errors today are not produced by negligence, lack of education, or lack of training. Rather, errors occur in our health care systems due to poor systems design and organizational factors, much as in any other industry. Health care workers are placed in systems and settings where errors are bound to happen. That is, the systems are designed to achieve a particular set of goals, but inadvertently produce a certain level of errors. For example, health care workers are sometimes expected to work 24-hour shifts to ensure patients are cared for and have some continuity of care, although it is known that overwork and fatigue lead to decreased mental concentration and alertness. These caregivers are expected to function in an environment that is not ergonomically designed for optimal work performance. They are expected to rely on their memories and deliver safe care without substantial investments in information technology or even the simple application of checklists. They often deliver care through a set of complex processes, although industry has shown that the probability of performing a task perfectly decreases as the number of steps in the process increases. Finally, they are expected to work in a climate where one error, even if not preventable, may mean a catastrophe or the end of a career.

By not improving the systems in which medicine is practiced, the health care industry as a whole has not advocated a culture of safety and is not well organized to tackle the challenge of improving patient safety. Only when the entire industry is able to make patient safety and the reduction of medical errors its first priority will errors in medical practice be reduced.

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A Global Challenge

The medical errors epidemic is a global problem. The United Kingdom, for example, has had some well-publicized difficulties with pediatric surgery outcomes in Bristol. British authorities estimate that 40,000 hospitalized patients die annually as a result of errors, which translates to a 3.7 percent overall rate of errors. The Australian Review of Professional Indemnity Arrangements for Health Care Professionals (Commonwealth Department of Human Services and Health, 1995) also found error to be a serious cause of morbidity and mortality. Australia, the United Kingdom, and Sweden are among the countries that have begun to address this issue. The British Ministry of Health is in the process of making funds available to researchers to investigate medical errors, and is re-engineering its clinical governance programs to provide mechanisms to improve patient safety. Australia has included medical errors as part of its focus on quality, and is initiating a national system for error reduction with enhanced reporting mechanisms. However, efforts to actually translate the limited research available into practice are still at an early stage, at best. Approaches are likely to vary across nations because of differences in health care organization, attitudes toward regulation, and views on patient information and confidentiality. The evidence informing those approaches, however, is likely to be more universal. As a global leader, the United States has a responsibility to the many countries that do not have the resources to devote to the study of this issue.

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Evidence of Errors

The Epidemiology of Medical Errors

Errors and other adverse events occur regularly in health care settings, but the causes, frequency, severity, preventability, and impact of these events on patient outcomes are not completely understood. A few studies have found an alarmingly high prevalence of adverse events and medical errors in some hospitals. In two large studies of hospital admissions, one in New York using 1984 data and another in Colorado and Utah using 1992 data, the proportions of admissions in which there were adverse events (defined as injuries caused by medical management) were 2.9 and 3.7 percent, respectively (Leape, 1991; Gawande, 1999). In the New York study, errors (defined as avoidable "mistakes in performance or thought") were determined to have caused more than half of the adverse events. However, the absence of standardized definitions of medical error, the lack of coordination and integration of systems to report and monitor errors, and the difficulty in distinguishing preventable errors from currently unavoidable adverse events hamper our understanding of this problem. It is unlikely that we can ever know the precise frequency with which errors occur in health care settings because we must rely on people to recognize that errors were made, to distinguish them from bad outcomes of appropriate treatment, and then to report them.

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Adverse Events and Medical Products Use or Misuse

Preventable injuries and deaths from pharmaceutical drugs are a growing problem that, according to some studies, represents a leading cause of death and patient harm in the United States (American Hospital Association, 1999; Centers for Disease Control and Prevention, 1999; Leape, 1991). Although the methods used to measure the rate of errors associated with the use of drugs have significant limitations, researchers have estimated that more than 50 percent of prescriptions are used incorrectly (Porter and Jick, 1977). Problems related to the use of pharmaceutical drugs account for nearly 10 percent of all hospital admissions, and significantly contribute to increased morbidity and mortality in the United States (Bates, 1995).

In the Harvard Medical Practices Study of adverse medical events (Leape, 1991), which was based on 30,195 randomly selected records from 51 hospitals in New York State, the researchers found that drug complications represented 19 percent of all adverse events. The researchers concluded that 58 percent of injuries and deaths due to drug reactions were preventable, and 27.6 percent of such complications were due to negligence. According to this study, antimicrobial drugs were the class of agents most commonly associated with adverse drug events. Misuse of antimicrobial drugs not only exposes individual patients to an increased risk of a poor treatment outcome, but also leads to the emergence and spread of drug-resistant microorganisms, which may place other patients and health care workers at risk of infection.

The specific problem of medication errors has drawn considerable public attention, since all such errors are preventable. Medication errors—mistakes in writing prescriptions, dispensing or administering drugs—are a subset of the larger category of errors involving drugs. In a caseĖcontrol study covering a 4-year period at a single hospital, it was determined that there was an almost 2-fold increase in the risk of death attributable to such errors. In the previously cited Harvard Medical Practice Study, 19.4 percent of all disabling adverse events were caused by drugs, of which 45 percent were due to medication errors. In that study, 30 percent of those with drug-related injuries died.

In addition to drug-related injuries and deaths that occur in hospitals, information is available indicating that preventable, drug-related injuries are also occur at a high frequency among out-patients. In a study of 1,000 ambulatory patients drawn from a community, office-based medical practice (Burnum, 1976), the researchers noted side effects from drugs in 42 patients (4.2 percent), including 23 who experienced preventable side effects. Well-understood drugĖdrug interactions are preventable, but there is evidence that physicians do not routinely screen for them, even when a patientís medication history is readily available. In a study of 424 randomly selected visits to a hospital emergency department (Beers, 1990), 47 percent of visits resulted in the patient receiving a prescription for a medication. In 10 percent of these instances, the new medication could potentially harm the patient due to an avoidable drug-drug interaction. In all of these cases, a medication history had been recorded and available to the prescribing physicians.

Thus, it can be seen that preventable and avoidable injuries due to drugs constitute a significant public health concern. The increasing use of drugs, the growing fragmentation of health care delivery, and the competing demands of an overburdened health care delivery system will, undoubtedly, accentuate these problems.

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Current Programs to Prevent Errors

Local Performance Measurement and Performance Improvement Systems. In the past decade, health care facilities and health plans have placed an increasing emphasis on improving health care quality. The impetus has come, at least in part, from patients, purchasers, accreditation agencies, and regulators determined to obtain the best value for the Nationís health care dollars. Today, virtually all health care organizations have programs to measure and/or improve health care quality.

Many hospitals and health plans collect and monitor data relevant to specific events (e.g., patient falls, failure to appropriately administer beta-blockers after myocardial infarction) or health outcomes (e.g., anesthesia mortality, length of stay after total hip replacement), which may or may not reflect medical errors. Hospitals commonly use these data for performance measurement or continuous quality improvement. Decisions about what will be monitored are usually based on the nature, severity, and importance of perceived problems at the local level, the feasibility of accessing data and formulating a response, and related incentives (e.g., meeting standards required for accreditation, anticipated cost-savings). Similarly, some hospital departments (e.g., pharmacy, nursing) use performance measurement to target treatment errors and other adverse events.

Performance measurement and quality improvement programs are less common and often less extensive outside of acute-care hospitals. Programs in risk management as well as more recently developed programs in what has been called "disease management" or "outcomes management," although aimed at improving health outcomes, generally have not specifically included error reduction in their scope. Occupational health or employee health programs, in addressing risks to health care workers, may also impact patient safety and quality of care. Overall, the degree to which these local programs address medical errors or other preventable adverse events and, more importantly, the extent to which they motivate changes that improve the overall heath status of patients, are not known. Part of the research agenda will be to see if market forces favor those health care organizations that improve patient safety.

Programs of infection prevention and control provide long-standing and successful examples of health care programs specifically designed to prevent adverse health events. These programs have been shown to reduce morbidity and mortality due to health care-associated infections. For this reason, infection control programs are mandated as a condition of accreditation for health care facilities. In hospitals, accreditation standards require a minimum number of trained infection control personnel and delineate specific program components. Such programs usually include ongoing monitoring (surveillance) of infection rates by trained infection control personnel using standardized case definitions, analysis of data with adjustment for facility and patient characteristics known to affect risk, comparison of local rates to aggregate benchmark data, prompt feedback of infection rates and trends to providers and decisionmakers, and targeted interventions that address specifically identified problems. This approach parallels that used in industrial continuous quality improvement programs and in industrial quality control. In nonhospital facilities, accreditation standards are less rigorous, and the composition and quality of infection control program is variable.

Regional and National Programs. Some regional and national external reporting systems to monitor errors and adverse health events already exist. FDA operates systems monitoring adverse events associated with drugs, medical devices, vaccines (co-managed with CDC), and blood and blood products. CDCís NNIS monitors health care-associated infections. Some State health agencies (e.g., those of New York, Massachusetts, Florida) also monitor targeted health events. Nongovernmental agencies (e.g., JCAHO and the U.S. Pharmacopeia, through their Sentinel Events and Medication Errors Reporting Programs, respectively) also operate error reporting systems.

Such external programs motivate local efforts to recognize and address problems, provide norms to which local efforts can be compared, and identify emerging problems (e.g., adverse drug events or manufacturing errors) that may require governmental or other system-wide response. For example, reported errors related to medical products can lead the FDA to require changes in package inserts and promotional materials, modifications in product packaging, and widespread dissemination of information through letters to health professionals and published alerts.

Most reporting systems have little or no enforcement authority to assure that reporting of errors is occurring consistently and completely. A recent report from the Department of Health and Human Serviceís (DHHS) Inspector General found that there is widespread underreporting to FDA's drug adverse event reporting system, despite the fact that more than 270,000 incidents are reported annually. In addition, even though these programs—some of which may be considered mandatory—may promise the opportunity to report errors and near-misses confidentially, those who submit reports (e.g., clinicians and hospitals) have expressed concern about their legal vulnerability in these reporting systems. Another reason for low rates of reporting in some systems is that information on how to prevent similar errors in the future is not fed back to the reporters. Therefore, these reporters see little benefit in completing and submitting reports.

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Accomplishments of Programs to Prevent Medical Errors

Despite the strikingly high incidence of medical errors documented in the IOM report, and the difficulties in obtaining reports on errors and near misses, there are remarkable examples of successful efforts to improve patient safety. Surgical anesthesia, which once had an error rate of 25 to 50 per million patients, reduced its error rate nearly 7-fold. (Orkin, 1993). The first step in reducing surgical anesthesia error rates was the collection of data that permitted a systems analysis of errors, rather than a hunt for "responsible" individuals. Through teamwork, practice guidelines, automation, procedure simplification, and standardization of many functions, anesthesiologists demonstrated that a properly designed system can either prevent mistakes or prevent mistakes from doing harm.

Another example of success is the advances in patient safety that have been achieved in the Department of Veterans Affairs (VA), through its Veterans Health Administration. For instance, a hand-held, wireless bar-coding system was introduced into VA and has reduced medication errors by 70 percent at relatively low cost (Gebhart, 1999). It is particularly interesting that this approach was adopted from a completely different industry—from observation of how Avis checked in returned rental cars. Similar behavioral and cultural changes must occur in other segments of the health care industry in order to address the patient safety issue fully.

Many Federal agencies have learned that the creation of a comprehensive knowledge base, rich in textual description of all aspects of errors occurrence, must be developed if preventive efforts are to be targeted and effective. One hopeful sign has been the development of private-sector organizations, such as the National Patient Safety Foundation (NPSF), the National Coordinating Council for Medication Error Reporting and Prevention, and JCAHO, which are promoting research and improvement initiatives focused on systems approaches to error reduction.

The occupational health field has demonstrated that human factors engineering can identify ergonomic concepts to prevent injuries to both patients and workers. Examples include curving the design of hallway corners to reduce the risk of injury from collisions, using mechanical lifts to prevent patient falls and employee back injuries, and reducing the number of scheduled work hours in a rotating shift to minimize the likelihood of errors resulting from fatigue and sleep deprivation.

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Insufficiency of Existing Programs

Effective error prevention systems need to be built on a foundation of locally directed and managed programs within health care organizations, complemented by coordinated, external support and guidance from Federal, State, and nongovernmental agencies and organizations. Within this framework, a comprehensive approach to error reduction would require specifically designated personnel working in or consulting with each health care setting to:

  1. Identify and monitor the occurrence of errors in targeted patient populations at greatest risk, and understand their root causes, especially those that are preventable.
  2. Analyze, interpret, and disseminate data to clinicians and other stakeholders.
  3. Implement error reduction strategies based on reanalysis and reworking of health care systems.
  4. As necessary, call upon experts with clinical, epidemiologic, and management training and experience for technical support and to conduct on-site investigations.
  5. Evaluate the impact of these programs on patient safety.

A number of factors reduce the effectiveness of existing programs to prevent medical errors. Performance measurement and improvement programs within health care organizations do not directly address the problem of medical errors. Programs that have been specifically developed to prevent medical errors often operate in isolation. In addition, programs such as infection control and employee health and safety typically receive low priorities within health care centers.

Efforts by external organizations to monitor errors also face limitations. A number of different programs exist to detect adverse health events, although no one system is designed to detect the full scope of medical errors.

Passive surveillance systems, such as the National Notifiable Diseases Surveillance System—in which health care providers and laboratories report incident cases of diseases (mostly infectious) to the State health department—while broad in scope and coverage, are often hampered by collection of incomplete data. Each State determines the diseases that are reportable, resulting in some differences across States. Furthermore, health care providers must remember which diseases are reportable, and take the time to report them.

Active surveillance, on the other hand, means soliciting case reports in a timely manner directly from potential reporting sources. Examples of this type of reporting include HIV/AIDS reporting, in which CDC provides funding to State and local health departments to support the surveillance process. These active surveillance systems provide more complete and accurate information, but are expensive to implement and maintain. Systems designed to hold organization or individual accountable for bad outcomes are commonly limited by underreporting of adverse events.

Although quality improvement programs within health care organizations could be enhanced or adapted to address errors, obstacles remain. The more serious are:

  1. Lack of awareness that a problem exists.
  2. A traditional medical culture of individual responsibility and blame.
  3. The lack of protection from legal discovery and liability, which causes errors to be concealed.
  4. The primitive state of medical information systems, which hampers efficient and timely information collection and analysis.
  5. Inadequate allocation of resources for quality improvement and error prevention throughout the health care system.
  6. Inadequate knowledge about the frequency, cause and impact of errors, as well as about evidence of effective methods for error prevention.
  7. Lack of understanding of systems-based approaches to error reduction (such as those used in aviation safety or manufacturing) and the perceived difficulty of adapting those approaches to the health care sector.

There are even greater barriers to error reduction in nonhospital settings, where the general absence of organized surveillance systems and lack of adequate personnel hinder local data collection, feedback, and improvement.

Lack of awareness. As stated earlier, the existence of medical errors has been known for some time. However, the fact that there has been very little success in reducing errors suggests that a general lack of awareness or alarm about errors is a factor in this failure. The awareness of the problem of medical errors and any subsequent solutions must be improved, not only among physicians, nurses, pharmacists, dentists, and other health care providers, but also among patients, policymakers, and the many other stakeholders of the health care community.

Barriers to partnership. The punitive and pejorative connotations of "error" as the object of investigation pose a potential barrier to the unfettered cooperation and collaboration of health care providers in establishing and managing effective error control programs. A cultural change needs to occur that will enable health care providers and leaders, as well as the public, to talk about errors and recognize that they are, in large measure, a result of faulty systems and faulty system design, not of individual failures.

Legal barriers. A system which supports learning from errors is dependent upon reporting, but fear of reprisal or legal action will dissuade many potential reporters. Assurances that the identity of reporters will be masked or never collected at all have been shown to enhance reporting in other industries (e.g., the ASRS). Disclosure of the individuals or organizations involved in an incident could also discourage reporting. There will remain instances, however, where criminal or negligent acts demand appropriate disclosure. The legal issues surrounding patient safety will have to be examined carefully to determine the best mechanisms to promote learning from errors while protecting the public.

Information systems and technical problems. To be practical, error prevention will need to rely on sophisticated management and clinical information systems, both as sources of data on adverse events and as a component of interventions to reduce errors, such as through the adoption of computer-based decision-support for health care providers. However, information systems in most health care organizations are neither sufficiently integrated nor flexible enough to serve either of these purposes. Technical support and research into information system desifgn will be required to address this problem.

Cost and structural concerns. Although considerable cost savings could be realized by effective reduction in medical errors, instituting such programs will require a substantial initial investment. In addition, the relative autonomy of departments within some health care institutions is a potential barrier to rapid organizational change and the adoption of new models and procedures needed to prevent errors.

Deficiencies in knowledge and understanding. The epidemiology of errors is not well understood. Standardized definitions of errors and adverse events need to be developed and the methods of collecting meaningful data require further study. Research is needed to help distinguish between adverse events due to errors, unavoidable consequences of treatment, and complications caused by a patientís underlying disease. The current paucity of fundamental and applied research on medical errors limits the tool kit of effective interventions that can enhance patient safety.

Lack of appropriate collaboration among disciplines. Because of the nature of medical errors, an effective response requires an integration of efforts across traditional occupational and scientific boundaries. The nature of the patient safety challenge requires synergy among scientific and technical disciplines, from human factors psychology to product design and delivery. This collaboration is needed at all stages of the effort to reduce errors and enhance patient safety—from research on its causes and remedies to implementation and partnership in its reduction and elimination. The response to medical errors by the health care system is hindered by the traditional focus of single disciplines on individual providers or on products, and even by poorly coordinated efforts among Government agencies and with the private sector.

Failure to apply a coherent strategy. The variety of medical errors and the multidimensional nature of the patient safety challenge demand a variety of approaches for improvement. Experience from other industries demonstrates, however, that successful interventions to address different types of errors can consistently result from the application of a coherent strategy that includes intolerance of high rates of error, development of tracking mechanisms, root cause analysis, the application of innovative resources and relationships to address the problem, and an institutional devotion to error prevention.

The QuIC concludes that systems designed to facilitate quality improvement through error reduction can generate effective, useful reporting if those individuals who report are assured of confidentiality, protected from legal liability resulting from the report, provided with timely feedback on data from the system, and are not unduly burdened by the effort involved in reporting.

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AHRQ Advancing Excellence in Health Care